jkenny23
Posts: 100
Joined: Sat Aug 19, 2017 12:49 pm
Delivery Date: 19 Sep 2017
Leaf Number: 009318

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Thu Dec 12, 2019 7:30 pm

All 3 values vary over time and can go up and down, especially weather related. It's pretty obvious here which you can correlate with the average temperature during the time when I recorded the values :)

Image

From the start until 1/3/18 or so the BMS was learning the capacity of the new pack (cells were replaced by Cor, you can find the other thread about this). After that it seems to have switched algorithm and behaved a little differently afterwards. So far I have not seen any trend towards decreasing life, I try and keep the car charged <=80% all the time (set it up to default to 80% unless I override).

I am still stuck with 5 capacity bars, despite my now ~87% SOH. It looks like Dala found a way to at least visually change the capacity bars though, so presumably a Muxsan enabled car could show a re-calculated true SOH: https://secondlifestorage.com/showthrea ... 1#pid57641

nlspace
Posts: 203
Joined: Mon Jun 05, 2017 10:21 pm
Delivery Date: 06 Jun 2017

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Thu Dec 12, 2019 9:15 pm

How far is your range? does the 5 bar capacity limit the range or power level (go to turtle).

jkenny23
Posts: 100
Joined: Sat Aug 19, 2017 12:49 pm
Delivery Date: 19 Sep 2017
Leaf Number: 009318

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Thu Dec 12, 2019 10:46 pm

nlspace wrote:
Thu Dec 12, 2019 9:15 pm
How far is your range? does the 5 bar capacity limit the range or power level (go to turtle).
My battery now is a 2013 87% SOH battery. The cells were swapped from a salvage Leaf. Range now is 50-60 miles depending on outside temp, my commute is mostly freeway 60MPH. The car behaves like it should with a battery of this health, the only difference is the display still shows 5 bars.

Before the swap, battery was ~20-30 miles if you were careful. I don't think it limited power level/acceleration, but of course I wasn't doing much of that since every kWH was precious :P

nlspace
Posts: 203
Joined: Mon Jun 05, 2017 10:21 pm
Delivery Date: 06 Jun 2017

range extender gone bad?

Mon Dec 23, 2019 2:52 pm

Anybody have links or info about a burned leaaf which used an 18650 extender pack in the trunk--was it discussed on this forum? was it a forum member that did this?

Supposedly an access hole was drilled thru the pack cover to add the wiring and either something shorted or water got into the main pack and caused the car to catch.

LeftieBiker
Moderator
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Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Mon Dec 23, 2019 2:56 pm

I don't think it was posted here - at least not recently.
Scarlet Ember 2018 Leaf SL W/ Pro Pilot
2009 Vectrix VX-1 W/18 Leaf modules, & 3 EZIP E-bicycles.
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WetEV
Posts: 3808
Joined: Fri May 04, 2012 8:25 am
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Location: Near Seattle, WA

Re: range extender gone bad?

Mon Dec 23, 2019 3:07 pm

nlspace wrote:
Mon Dec 23, 2019 2:52 pm
Anybody have links or info about a burned leaaf which used an 18650 extender pack in the trunk--was it discussed on this forum? was it a forum member that did this?

Supposedly an access hole was drilled thru the pack cover to add the wiring and either something shorted or water got into the main pack and caused the car to catch.
Yes, I remember reading that in MNL. But I can't find the original posting.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red
2019 eTron Blue

mux
Posts: 297
Joined: Sat Jan 13, 2018 3:52 am
Delivery Date: 13 Oct 2011
Leaf Number: 6177

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Tue Dec 24, 2019 3:28 am

There are two postings that I've definitely seen in the past but cannot find now.

One was the one described here - somebody added an access hole and most likely water got in and caused the car to go up in flames.
Another was somebody who I don't remember even added extra capacity (but he might have), but definitely removed the top shell, put it back and probably also had water ingress. That car went up in flames during a fast charging session.

I've recounted these stories to other people, but recently wanted to show the original stories in a blog/vlog and can't find them anymore. If anybody has clues, there's now two people searching for these.

nlspace
Posts: 203
Joined: Mon Jun 05, 2017 10:21 pm
Delivery Date: 06 Jun 2017

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Tue Dec 24, 2019 6:17 am

Found a couple of videos but no details. Looks to me that fire started where the added wires entered the pack (sharp edges slice insulation?), oem pack did not catch

https://youtu.be/2cIo95W-vfE 18650 extender pack fire

North Texas street fire, no details: https://youtu.be/8PUG-ldjD48

What is that burning mass on the ground (extender module?) Look at the intensity of the fire, and how far out the bottom edge of fire and smoke extends from the back seat window--what in the car could burn like that? i think this was an extender fire also--extender pack in the back seat and maybe in the front seat too. Backpack and laptop over in the grass?

Image

Flower Mound TX

Image

coulomb
Posts: 93
Joined: Thu Oct 09, 2014 5:08 pm
Delivery Date: 07 Mar 2015
Leaf Number: 200445
Location: Brisbane, Australia

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Wed Dec 25, 2019 4:04 pm

nlspace wrote:
Tue Dec 24, 2019 6:17 am
Found a couple of videos but no details. Looks to me that fire started where the added wires entered the pack (sharp edges slice insulation?), oem pack did not catch
Thanks for the finds.

In the case of the first video/stills, it looks to me that the extra wires included many thin wires. So it appears that they paralleled cells so that the original BMS would protect the added cells as well as the original cells. That saves the cost of an additional BMS, but I'm guessing more importantly it avoided the need to integrate the two BMSs.

If I'm right, that's 97 thin and unfused wires with complete battery potential between the end two wires, and anything from one to 95 cells worth between any other pair of wires. It's bad enough when the manufacturer does this with short wires professionally crimped and with industrial connectors all within the sealed battery shell, but to connect all those wires to a home made battery, regardless of the quality and care involved, is just begging for trouble to me.
I actually prefer the Mitsubishi iMiev cell top BMS design, to avoid all those unfused wires altogether.

Any clues as to whether they really did have many thin wires would be appreciated.

Also @mux, does your extender pack do this, or does it have its own BMS?

[ Edit : even when the contactors are off, these wires would be live 24/7. Even with the safety disconnect out, some pairs of wires would have up to 3/4 of the pack voltage between them, since the Leaf disconnect splits the battery 3/4 and 1/4. So it's never safe. Again, all if and only if I'm right about those wires. ]
2012 Leaf with new battery May 2019. New to me June 2019.

jkenny23
Posts: 100
Joined: Sat Aug 19, 2017 12:49 pm
Delivery Date: 19 Sep 2017
Leaf Number: 009318

Re: Extra Battery, How to Integrate with 24kWh Traction Battery?

Wed Dec 25, 2019 4:26 pm

coulomb wrote:
Wed Dec 25, 2019 4:04 pm
Any clues as to whether they really did have many thin wires would be appreciated.

Also @mux, does your extender pack do this, or does it have its own BMS?
Scary indeed having that many small wires. Would be easy to fuse the main connection at the original cells, but that design is just bad news all around. My plan would be to interface my extender pack with a "real" Leaf BMS, just a second model which you can pick up surplus for around $100. Where else are you going to find a 96 channel high resolution ADC with isolation and balancing (as low as it is) for that price, crazy! Easy to tie to another Bluetooth OBDII for a graphical representation too. There's also a user on the DIY electric car forums Wolftronix who has done a full "brain transplant" on the Leaf BMS replicating all the original functions, to give another option.

I'll let Mux answer but from what I saw in his videos, the modules he's using are each containing their own balancing BMS which is standalone but can all be communicated with for more detail.

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